Battle of Atherstone

The Battle of Atherstone was a battle of the Viking invasions of England which occurred in 885 near Atherstone, Warwickshire, England. The Mercian ealdorman Aethelmund of Carlea repelled an invasion of Mercia by a Viking army of 3,150 warriors under Hallvard Thormarsson. In the ensuing battle, the Mercian shield walls held back the Viking attack, and the Mercians then engaged in a ruthless pursuit of the fleeing Vikings, slaughtering them.

Background
During the 880s, the arrival of the Viking leaders Sigefrid and Erik Thurgilsson in England with their Francian Viking army led to an increased number of clashes between the Anglo-Saxons and the Danes along Watling Street, the boundary dividing Saxon Mercia from the Danelaw-ruled portion of the kingdom. The brothers' seizure of London in 884 enabled them to establish a chokehold on the River Thames. The Viking warlord Hallvard Thormarsson grew confident in the success of a massive raid into Mercia, correctly believing that Lord Aethelred of Mercia was focused on the recapture of London and on matters to the south. Hallvard led an army of 3,150 Viking warriors (most of them peasants from his lands) across Watling Street and into Mercia, so Ealdorman Aethelmund of Carlea assembled Mercia's most experienced and best-trained warriors to face the Viking onslaught not far from the Mercian capital of Tamworth, joining battle at Atherstone.

Battle
The Mercians layed their army in three rows, with the spearmen and swordsmen forming the first line of defense, flanked by mailed cavalry on either side. Behind them were the archers and javelinmen, and behind these missile troops was Aethelmund and his retinue of bodyguards. The Danes were greeted with arrow fire and shield wall formations as they approached the Mercian army, and the overextended Mercian line was able to close in on the Danes' flanks to envelop their army. The Mercian cavalry charged the Danish hunters who were behind their army's main line, demoralizing the frontline troops. The cavalry then charged the Danes from the rear, causing the Danes to be slaughtered from multiple sides. The Danish army collapsed as the Mercian wings and their cavalry entrapped them, and the Mercians ruthlessly pursued the Danish warriors. Of the 3,150 Danes who had initiated the raid, 2,897 were dead on the battlefield, while the Mercians lost 553 men. The battle was a decisive Mercian victory, as Hallvard had fallen, his army was destroyed, and the Danish raid had failed.